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How do we make maps?

Having been trained as cartographers, it’s second nature to us but to others it can seem a daunting task. Yes, anyone can sketch out a rough map on a scrap of paper but, if you want something a little better and a little more accurate, it gets slightly more complicated.

Take a few minutes out of your day while we show you how we produce maps at PCGraphics.

First, a glimpse into the not so distant past when all maps we created ‘manually’. This meant working over a light box (like a glass topped table with lights underneath) where every line was drawn or ‘scribed’ using pen-like instruments with chiseled sapphire points (yes, it sounds like something that would be used in the stone-age but this was only a couple of decades ago). Text, or ‘type’, was placed onto a map manually using a photographic method of typing the words (street names etc) onto very thin film which was then coated on the reverse with a layer of wax and applied to the map sheet. All the elements of the maps were combined together, in negative form, in a reprographics studio. Eventually, four ‘final films’ of the map were created and these were used to make a proof or to print from.

Obviously, this was extremely laborious and costly and, if you made a mistake, it could mean hours or even days wasted. So, when computers, and especially the Apple Mac, arrived it didn’t take long for cartographers to switch to computer created maps.

End of, albeit a rather brief, history lesson.

So, today, cartography tends to be split between GIS (Geographic Information System) maps and maps which are simply graphics. GIS maps have a lot more intelligent data behind them in the form of databases whereas graphical maps are simply that, graphics.

At PCGraphics we specialise in graphical maps (our name gives a clue to that!) and our maps are usually created in a vector drawing programme called Illustrator. Vector simply means that the drawing is made up of points, any of which can be adjusted, moved, deleted etc. Vector artwork is scalable and can be enlarged without becoming pixillated.

The map portion below shows the blue keylines and points which are used to create a vector map. These are what the map is made up of and don’t print in the final version.

Ok, we want to draw a map and we’ve spent over £500 on a licence for the Illustrator programme sitting on our shiny new Mac or PC. What now?

The first decision is what to base the map on. There are several choices for this. Taking the example above, a map of Oxford in the UK, we would need to use one or more of the following

aerial photography

out of copyright mapping or other copyright free information

Ordnance Survey data

Prior to April 2010, we would probably have used aerial photography as the basis for creating the map. We would have imported the photography into Illustrator and traced all the roads and other linework from the photographs. Obviously aerial photos don’t come with the names of towns or roads attached, so the next stage would be to send some hapless cartographer out into the wilds of the City of Oxford armed with a pen, paper and clipboard to note down the name of every road or other feature appearing on the map. Nice on a warm, sunny day but pretty miserable when it rained or snowed. At the end of this we would have had what is termed a ‘royalty free’ map. This meant that everything on the map was generated by ourselves and nothing was taken from a copyright source.

This all changed in April 2010 however when large chunks of Ordnance Survey data were opened up for commercial use. Whereas, previously, the O.S. would have charged an arm and a leg, and sometimes more, in royalty payments for using the data we in the UK had already paid for in our taxes, it was now all available free.

So, today, a map of Oxford would probably be based on Ordnance Survey data with no royalties or licence fees to pay. The production costs are likely to be less too than the royalty free method outlined earlier. Oh, and there’s less chance of cartographers getting sunburnt or caught in a rainstorm too! A win/win situation.

This still leaves the drawing in Illustrator to do. Illustrator is one of those programmes which have a steep learning curve. Quite honestly, if there was a viable alternative we’d be using it. There used to be an alternative called Freehand, which was much more intuitive to use, but Adobe, who make Illustrator, bought Freehand and swiftly dumped it.

Don’t get me wrong, you can make great maps in Illustrator, it’s just that Freehand was so much easier to use. But hey, who needs an easy life anyway?

Illustrator, as do most vector software, lets you work in layers. A map of Oxford for instance can have 100+ layers, any of which can be turned on or off and the data on that layer manipulated.

(Above – Just a few of the layers on a typical map created in Illustrator)

A paper proof can either be printed straight from the Illustrator file or, more commonly these days, the file is exported to a JPEG or PDF and sent by email for the client to approve. Once this is done, and any changes made, we’re ready to send the final file to the client or printer.

So, that’s it in a nutshell. Ok, so there’s a few more twists and turns along the way, as there is with most things, but that’s the basics of it.

Cartography, it has to be said, is far easier these days than it used to be even in the early 1990s. It’s much more efficient and a lot, lot cheaper than the old manual methods. It’s still an enjoyable career and one we only (very) occasionally regret entering.